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In this brave new world of the software defined datacenter, traditional corporate IT silos defined around storage, compute, and networking are now more blended than ever. I don’t think that is really news to anyone at this point. Working in a very large multi-national conglomerate corporation, I can certainly tell you a few things about the silo effect. It has evolved and become a standard in most corporations for a very good reason: change control, and a need for a defined scope of responsibilities. This environment however is no longer viable in the world of cloud computing. When the user has developed the taste/need for instant gratification, they expect...

I am in the early design phase of a very large-scale (global) private cloud deployment. One of my design challenges is centered around multi-site availability. I need to be able to extend a layer-2 domain across multiple sites. Eventually I want to be able to get to the point were I can orchestrate a “follow-the-sun” model where a user or business unit can instantiate a service, application, (whatever), and have the option to enable that application to migrate globally to different data centers as regions come online, and source traffic begins to shift throughout the day. After VMWorld this year, I was very excited with the advancements made in...

I sat the VCAP5-CID (Cloud Infrastructure Design) exam yesterday, and thankfully managed to pass. I wanted to throw together a quick post explaining my exam experience and the preparation work involved. I hope that this is of assistance to someone out there who may be considering sitting this exam. First off, this was a challenging exam. In terms of difficulty when compared with the other VCAPs I have taken, I would rank this one at the top. This exam is about 3.5 hours and I was under the 3-minute mark when I submitted the last answer. What made this exam the most challenging for me was the networking portions....

I sat the VCAP5-DCA exam a few weeks ago, and I am happy to report that I received the notification yesterday that I passed. I would like to document my exam experience here to help others that may be preparing to sit this exam. The primary challenge in this exam is time. It is essentially a 4 hour exam, and it is a race against the clock the entire time. The exam is 100% lab. This means that you are remote-connecting to a real environment and you are expected to make the necessary configuration changes to that environment for each task. There are 26 tasks in total, and each...

As I am now in the preparation stage for the VCAP5-DCA exam, I wanted to take a few minutes to post the list of resources that I am using to prepare. Hopefully this will be of assistance to someone else out there also preparing for the same exam. First, a few notes about the exam: The time allotted for the exam is 225 minutes. Like the DCD exam, if you are taking this in a non-English speaking country, you are allowed an extra 30 minutes. The Exam is 100% lab. There are no multiple choice or drag/drop questions, everything happens in a lab environment. You will be given around...

I had originally planned on sitting this exam at the end of the month, but I had gotten to the point in my studying that I felt like my brain had absorbed all it was going to, so I went ahead and took the plunge. I’m happy to say that I passed with flying colors. Experience This time around I knew what to expect going in. I managed to finish the exam with more than an hour left on the clock. This had a lot to do with the fact that I was much more familiar with the design tool and how to manipulate the various objects. The design...

With the recent news that the one and only Frank Denneman – VMware’s Senior Architect Technical Marketing – is leaving the company for the relatively unknown start-up “PernixData” it’s bound to raise some eyebrows and get people talking. It certainly caused me to take a closer look at the company and their product. I’ll try to summarize here what it is aiming to accomplish (to the best of my knowledge), and why it is so exciting for us virtualization geeks. Arguably one of the most challenging pieces to get correct in any virtualization design architecture is shared storage. You primarily need to plan for two things: capacity and performance....

Last week I spent some time visiting the VMware campus in Palo Alto, California. I can’t discuss the purpose of my visit due to a non-disclosure agreement with VMware, but I believe I can safely comment on my impressions of the company and the staff that I met. Actually I visited several Silicon Valley companies while I was there (Facebook, Google, HP, Apple, to name a few), and it was an eye-opening experience to say the least. But first, lets talk about VMware. This is my first visit to the Palo Alto campus, and I have to say, It is as huge as it is beautiful. It is tucked...

So I sat for the VCAP5-DCD exam yesterday and managed to fail it by just a few points. I want to document my exam experience here to hopefully help anyone else attempting this certification. First off, just to summarize – this test is composed of 100 questions. Most of these will be multiple choice, there will be several drag-drop questions, and between 5-8 design questions (where you have to read a case study and use the in-exam design tool to create a Visio-like design). Each of the design questions took me about 15-20 minutes each. I had 6 of them on this exam. The exam is about 4 hours, and...

So this post is a little different from my other posts. As I am approaching the 20 year mark in my professional IT career (I started in ’93 building and customizing Wildcat and Renegade BBSs), I have done some reflecting. I have identified some things that I could have done better, and some things that I did pretty well. I’ve used that to come up with 10 things that I would tell my younger self if I had the opportunity. I’ve heard it said that advice is simply a form of nostalgia (and that is likely the case here), but with any luck perhaps this will be of some...

I want to discuss multiple NIC vMotion in vSphere 5. I feel it is one of the best features in this release and certainly deserves a close look in any environment which makes use of vMotion. Including (of course) any DRS enabled cluster. Before I start, I want to reference two excellent blog posts on this subject by Frank Denneman and Duncan Epping. I will be essentially summarizing their posts here as well as adding my own data from several host evacuation tests I have performed. Frank’s article is here. Duncan’s article is here. What is it? Multi-NIC vMotion is exactly what it sounds like. It provides the ability to use multiple network...

Just wanted to write a quick post about the merits of EVC, and one of its little known advantages. Well, maybe calling it “little known” is an overstatement, but at the very least I would say it is widely overlooked. EVC – As you probably know stands for “Enhanced vMotion Capability.” When you enable EVC on a cluster, you are essentially setting a baseline CPU compatibility level for all hosts in that cluster. This is beneficial for later when you may add a new hosts with a newer processor generation. Note that it will not allow you to cross the Intel/AMD gap, but for processors within the same family, you will...

I have been recently mulling over the potential benefit of LACP in some of our environments. I want to discuss how LACP is implemented in vSphere, its limitations, and the potential benefits that I see in its use. I will also go over the process for enabling LACP from the vSphere side of things. Beginning with vSphere 5.1, VMware supports Link Aggregation Control Protocol (LACP) on distributed switches (vDSs). LACP, as I am sure you are already aware, allows the bundling together of multiple physical links to form a single logical channel. The purpose here is to provide more efficient network redundancy and failover (as well as increased available...